Systematic review: the association between symptomatic response to proton pump inhibitors and health‐related quality of life in patients with gastro‐oesophageal reflux disease

Aliment Pharmacol Ther 2011; 34: 618–627

Summary

Background Some patients with gastro‐oesophageal reflux disease (GERD) experience persistent reflux symptoms on proton pump inhibitor (PPI) therapy. The relationship between persistent reflux symptoms and health‐related quality of life (HRQoL) is unclear. Aim To assess the relationship between persistent reflux symptoms on PPI therapy and HRQoL in patients with GERD. Methods Systematic searches were conducted in PubMed and Embase. Eligible studies had to have used psychometrically evaluated patient reported outcome instruments to assess HRQoL. Results Nine studies were included; supplementary data were obtained for four of these. The effect of persistent reflux symptoms despite PPI therapy on physical HRQoL was assessed in seven studies and that on mental HRQoL in five studies. Compared with patients whose reflux symptoms responded to PPIs, those with persistent symptoms had, on average, 8–16% lower scores for physical health (five studies) and 2–12% lower scores for mental health (three studies). Three studies included data on the effect of baseline HRQoL on subsequent symptomatic response to PPI therapy. Patients with persistent symptoms had clinically relevant lower psychological well‐being at baseline compared with those whose symptoms responded to PPIs (average score difference: 7%; two studies). High anxiety levels at baseline seemed to be an important aspect of persistent symptoms. Conclusions Persistent reflux symptoms on PPI therapy are associated with reduced physical and mental HRQoL, while reduced mental HRQoL at baseline seems to impair symptomatic response to PPIs. HRQoL may need to be considered alongside reflux symptom frequency and severity when making decisions about disease management.     

Evolving pharmacological approaches in gastroesophageal reflux disease

Introduction: Proton pump inhibitors (PPIs) have considerably improved quality of life in patients with gastroesophageal reflux disease (GERD). However, many patients remain symptomatic despite standard PPI therapy. Areas covered: This review focuses on evolving therapeutic strategies related to the pathophysiological processes of GERD and insufficient response to PPIs. Several clinical trials evaluated new PPI formulations and newer types of acid-suppressive drugs. These studies have evaluated traditional end points in GERD, but have not shown clinical superiority to current PPIs. Novel therapeutic strategies targeting underlying mechanisms of GERD, such as transient lower esophageal sphincter relaxations (TLESRs) and esophageal hypersensitivity, are being developed for add-on therapy to PPIs. Prokinetic drugs may also have some potential in the add-on treatment of GERD with insufficient response to PPIs. Add-on studies are hampered by insufficient information on optimal patient selection and lack of established end points. Expert opinion: Newer drugs for symptomatic control in GERD have largely focused on improved acid suppression, without evidence of clinical superiority. Drugs targeting esophageal motility and sensitivity to be used as add-onc therapy in PPI insufficient responders have not reached Phase III trials to date, due to difficulties with patient selection, tolerability and end points.     

Evolving drugs in gastroesophageal reflux disease: pharmacologic treatment beyond proton pump inhibitors

Importance of the field: Despite the clinical success of proton pump inhibitors to treat gastroesophageal reflux disease (GERD), for the majority of patients in both gastroenterology and primary care clinics there is still a substantial group of patients (up to 40% in some studies) who do not completely respond symptomatically to a standard dose of proton pump inhibitors (PPIs). Specific explanations for these PPI noncomplete responders included transient lower esophageal sphincter relaxations (TLESRs), sensitivity to weakly acidic and/or alkaline reflux, large volume of reflux and esophageal hypersensitivity. There is a clear need for GERD therapies beyond the PPIs.

Areas covered in this review: These drug classes include the GABA_B receptor agonists (including lesogaberan and arbaclofen placarbil), mGluR5 receptor antagonists, P-CABs, cholecystokinin₂ antagonists and add-on therapies to PPIs including mosapride and rikkunshito.

What the reader will gain: Both physicians and patients are eagerly awaiting the development and FDA approval of a new class of anti-GERD medications targeting distinct mechanisms. This article provides information on pharmacologic strategies, clinical trials and side-effect profiles on several of the most promising and heavily researched compounds being developed today for the treatment of GERD symptoms and inflammation. Hopefully, this important research will help a large group of PPI noncomplete responding patients receive symptomatic relief and reduce esophageal inflammation through a unique pharmacologic mechanism in the near future.

Take home message: The treatment of GERD has greatly improved with the PPI class of therapy. Despite excellent success, there is a sizeable population of patients who do not have adequate response to therapies directed only at acid suppression. Emerging new pharmacologic treatment options show promise in further advancing the treatment success of GERD.     

Timely confirmation of gastro-esophageal reflux disease via pH monitoring: estimating budget impact on managed care organizations*

ABSTRACT

Background: Current guidelines recommend the use of pH monitoring to confirm the diagnosis of acid reflux in patients with a normal endoscopy. This analysis evaluated the financial impact of pH monitoring with the wireless pH capsule on a managed care organization (MCO) in the United States.

Methods: A decision model was constructed to project total 1-year costs to manage GERD symptoms with and without the adoption of wireless pH capsules in a hypo­thetical MCO with 10?000 eligible adult enrollees, of whom 600 presented with GERD-like symptoms. Costs of GERD diagnosis, treatment, and symptom management for those in whom a GERD diagnosis was ruled out by pH monitor­ing were assessed. The incremental per-member-per-month (PMPM) and per-treated-member-per-month (PTMPM) costs were the primary outcomes. Data sources included literature, expert input, and standardized fee schedules.

Results: An increase of 10 percentage points in the use of pH monitoring with wireless pH capsules yielded incremental PMPM and PTMPM costs of $0.029 and $0.481, respectively. The costs of proton pump inhibitor (PPI) therapy to the plan dropped to $236?363 from $238?086, while increases were observed in pH monitor­ing (from $16?739 to $21?973) and non-GERD therapy costs (from $1392 to $1740). The results were sensitive to the percentage of patients requiring repeat endoscopy before wireless pH monitoring and the cost of PPIs.

Conclusions: Timely and increased use of pH monitor­ing as recommended in published guidelines leads to less unnecessary use of PPIs with a modest budgetary impact on health plans.     

Review article: current perspectives on hypergastrinaemia and enterochromaffin-like-cell hyperplasia

Rabeprazole, a new benzimidazole proton pump inhibitor (PPI), is among a class of agents known to be very potent inhibitors of gastric acid secretion. PPIs inhibit hydrogen-potassium adenosine triphosphatase activity on the luminal surface of the parietal cell, effectively blocking the final common pathway for gastric acid secretion. Raising gastric pH stimulates the production of gastrin by G cells in the antrum of the stomach, which can lead to enterochromaffin-like (ECL)-cell hyperplasia. In the past, these changes have been viewed with concern, particularly in the light of studies in rats indicating that hypergastrinaemia and ECL-cell hyperplasia induce gastric carcinoid tumour formation. All available clinical data indicate that long-term PPI use does not lead to carcinoid tumour formation in humans. In fact, both serum gastrin elevation and ECL-cell hyperplasia are now generally viewed as normal physiological responses to gastric acid suppression. Serum gastrin concentrations, in particular, correlate well with gastric acid suppression, which has led to the use of gastrin response by some investigators as a surrogate marker of antisecretory effectiveness. Long-term tolerability data indicate that PPIs have a favourable side-effect profile. Data obtained from patients receiving acute or long-term maintenance rabeprazole therapy support this conclusion. Furthermore, neither animal nor human data obtained with rabeprazole suggest a significant risk for neoplastic changes secondary to hypergastrinaemia.     

Programme of stepping down from twice daily proton pump inhibitor therapy for symptomatic gastro-oesophageal reflux disease associated with a formulary change at a VA medical center

BACKGROUND: In July 2001, our Veterans' Affairs hospital changed its formulary proton pump inhibitor (PPI) from lansoprazole to rabeprazole. All patients previously receiving lansoprazole 30 mg twice daily were switched to rabeprazole 20 mg once daily. AIM: To determine if patients with gastro-oesophageal reflux disease (GERD), who were previously managed on lansoprazole 30 mg twice daily, could be maintained on rabeprazole 20 mg once daily. PATIENTS AND METHODS: Four hundred and thirty-five patients had received lansoprazole 30 mg twice daily for at least 12 months before the formulary change. Medical records were reviewed for 12 months before and after the formulary change. RESULTS: There were 432 men and three women with a mean age of 66.7 years (range: 38-91). Two hundred and twelve patients were excluded. Of the remaining 223, 111 (50%) were maintained successfully on rabeprazole 20 mg once daily. Twenty-three (10%) stayed off all acid suppression during follow-up. The number of endoscopies and clinic visits did not significantly change during the follow-up. Fifty-six percent who had erosive oesophagitis failed a dose taper compared with 31% of those with endoscopy-negative GERD (P<0.025). CONCLUSIONS: Most patients receiving twice daily PPI therapy for GERD could be maintained on once daily PPI or no acid suppression for 12 months of follow-up. Dose reduction was more successful in those without erosive oesophagitis.     

Emerging drugs for gastroesophageal reflux disease

Proton pump inhibitors (PPIs) are very effective and safe drugs for the treatment of erosive and non-erosive gastroesophageal reflux disease (GERD). Nevertheless, a significant proportion of GERD patients (30 – 40%) continue to suffer from symptoms during PPI treatment, which has stimulated the search for better drugs. Improvement of PPI pharmacokinetics and pharmacodynamics has been the main focus of drug development in the past decade with the ultimate goal of optimizing acid inhibition. New inhibitors of the proton pump with a longer half-life, acting faster and longer, have been developed, including potassium-competitive acid blockers. Recent data, however, suggest that the therapeutic efficacy of acid suppression may have reached its maximum and other mechanisms may have to be targeted to further improve symptom control. Potential drugs interacting with different targets are reflux inhibitors such as GABA_B receptor agonists and mGluR5 antagonists. These agents reduce the number of transient lower esophageal sphincter relaxation thereby reducing both acid and non-acid reflux. Theoretically, visceral analgesics to modulate visceral perception or even growth factors to enhance mucosal healing may be other emerging drugs to treat GERD.     

Proton pump inhibitors: the beginning of the end or the end of the beginning?

Despite the dramatic success of pharmacological acid suppression in healing peptic ulcers (PUs) and managing patients with gastro-esophageal reflux disease (GERD) a number of challenges remain in the management of acid-related disorders. Several new drugs are currently being investigated to provide a significant advance over current treatments. These include new drug formulations, novel proton pump inhibitors (PPIs) as well as potassium-competitive acid blockers (P-CABs), which have already reached clinical testing. Some others (like NO-releasing antisecretory compounds) are still in preclinical development and require proof of concept in humans. While H(2)-receptor antagonists (especially soluble or OTC formulations) will become the 'antacids of the third millennium' and will be particularly useful for on-demand symptom relief, clinicians will continue to rely on PPIs to control acid secretion in GERD and other acid-related diseases. Since an increasing proportion of patients fail to respond to the best PPI treatment, more potent and long-acting drugs and more effective regimens are needed.     

Evolving pharmacological approaches in gastroesophageal reflux disease

Introduction: Proton pump inhibitors (PPIs) have considerably improved quality of life in patients with gastroesophageal reflux disease (GERD). However, many patients remain symptomatic despite standard PPI therapy.

Areas covered: This review focuses on evolving therapeutic strategies related to the pathophysiological processes of GERD and insufficient response to PPIs. Several clinical trials evaluated new PPI formulations and newer types of acid-suppressive drugs. These studies have evaluated traditional end points in GERD, but have not shown clinical superiority to current PPIs. Novel therapeutic strategies targeting underlying mechanisms of GERD, such as transient lower esophageal sphincter relaxations (TLESRs) and esophageal hypersensitivity, are being developed for add-on therapy to PPIs. Prokinetic drugs may also have some potential in the add-on treatment of GERD with insufficient response to PPIs. Add-on studies are hampered by insufficient information on optimal patient selection and lack of established end points.

Expert opinion: Newer drugs for symptomatic control in GERD have largely focused on improved acid suppression, without evidence of clinical superiority. Drugs targeting esophageal motility and sensitivity to be used as add-onc therapy in PPI insufficient responders have not reached Phase III trials to date, due to difficulties with patient selection, tolerability and end points.     

Meta‐analysis: the effects of placebo treatment on gastro‐oesophageal reflux disease

Aliment Pharmacol Ther 2010; 32: 29–42

Summary

Background There appears to be a significant placebo response rate in clinical trials for gastro‐oesophageal reflux disease. Little is known about the determinants and the circumstances associated with placebo response in the treatment of gastro‐oesophageal reflux disease (GERD). Aims To estimate the magnitude of the placebo response rate in randomized controlled trials for GERD and to identify factors that influence this response. Methods A meta‐analysis of randomized, double‐blind, placebo‐controlled trials, published in English language, which included >20 patients with GERD, treated with either a proton pump inhibitor or H₂‐receptor antagonist for at least 2 weeks. Medline, Cochrane and EMBASE databases were searched, considering only studies that reported a global response for ‘heartburn’. Results A total of 24 studies included 9989 patients with GERD. The pooled odds ratio (OR) for response to active treatment vs. placebo was 3.71 (95% CI: 2.78–4.96). The pooled estimate of the overall placebo response was 18.85% (range 2.94%–47.06%). Patients with erosive oesophagitis had a non‐significantly lower placebo response rate than patients without it (11.87% and 18.31%, respectively; P = 0.246). Placebo response was significantly lower in studies of PPI therapy vs. studies of H₂ RAs ( 14.51% vs. 24.69%, respectively; P = 0.05). Conclusions The placebo response rate in randomized controlled trials for GERD is substantial. A lower placebo response was associated with the testing of PPIs, but not the presence of erosive oesophagitis.     

Esomeprazole 20 mg maintains symptom control in endoscopy-negative gastro-oesophageal reflux disease: a controlled trial of 'on-demand' therapy for 6 months

BACKGROUND: Most patients with gastro-oesophageal reflux disease (GERD), regardless of endoscopic status, suffer symptomatic relapse within 6 months of stopping acid suppressant therapy. AIM: To assess the efficacy of 'on-demand' treatment of GERD with esomeprazole, the first proton pump inhibitor developed as an optical isomer. METHODS: In this multicentre, double-blind study, 342 endoscopy-negative GERD patients demonstrating complete resolution of heartburn during the final week of a 4-week treatment period with esomeprazole 20 mg or omeprazole 20 mg once daily were randomized to receive esomeprazole 20 mg or placebo on demand (maximum of one dose per day) for a further 6 months. Use of rescue antacids was permitted. RESULTS: All 342 patients (191 males), aged 19-79 (mean 49) years, were evaluable in the intention-to-treat analysis. The proportion of patients who discontinued treatment due to insufficient control of heartburn was significantly higher among placebo compared to esomeprazole recipients (51% vs. 14%; P < 0.0001). Patients randomized to esomeprazole on-demand therapy remained in the study longer than those in the placebo group (mean 165 vs. 119 days). Over 50% took the study medication for periods of 1--3 consecutive days (esomeprazole) or 4--13 consecutive days (placebo). Use of antacids was > 2-fold higher among placebo recipients. The frequency of adverse events was similar in the two groups, when adjusted for time spent in the study, as were the clinical laboratory profiles. CONCLUSIONS: On-demand therapy with esomeprazole 20 mg is effective and well tolerated in maintaining symptom control in endoscopy-negative GERD.     

Review article: Helicobacter pylori and gastro-oesophageal reflux disease-clinical implications and management

A significant proportion of patients with gastro-oesophageal reflux disease (GERD) have Helicobacter pylori infection, but it is unclear whether or not H. pylori should be treated in this clinical setting. The aim of this review was to critically assess the relationship between H. pylori and GERD and its potential implications for the management of GERD. Data for this review were gathered from the following sources up to April 1998-the biomedical database MEDLINE, a detailed review of medical journals, and a review of abstracts submitted to relevant international meetings. On average, 40% of GERD patients carry H. pylori infection, with a reported infection prevalence ranging from 16% to 88%. To date, there has been no reported controlled trial of effective H. pylori therapy in GERD. GERD has been reported to develop de novo following the cure of H. pylori in peptic ulcer disease. In the presence of H. pylori, proton pump inhibitor therapy appears to accelerate the development of atrophic corpus gastritis, a potentially precancerous condition. Conversely, proton pump inhibitor therapy seems to become less effective after cure of H. pylori. The mechanisms underlying these important contrasting phenomena are poorly understood. The relationship between H. pylori and GERD is complex, and it is difficult to give definitive guidelines on the management of H. pylori infection in GERD. Controlled trials of H. pylori therapy in GERD are urgently needed, as well as further long-term data on both the natural history of gastric histopathological changes in the H. pylori-positive GERD patient treated with proton pump inhibitors, and the impact of H. pylori status on the clinical efficacy of antisecretory therapy. Pending these data, it is perhaps advisable to advocate cure of H. pylori in young patients with proton pump inhibitor-dependent GERD who, in the absence of anti-reflux surgery, are faced with the likelihood of long-term medical therapy.     

NSAID-induced peptic ulcers and Helicobacter pylori infection: implications for patient management.

The conflicting data about the influence of Helicobacter pylori infection on the ulcer risk in patients receiving NSAIDs can be accounted for by the heterogeneity of study designs and the diversified host response to H. pylori. Factors that will affect the outcome include the choice of H. pylori diagnostic tests, previous ulcer complications, concurrent use of acid suppressants, NSAID-naive versus long-term users, low-dose aspirin (acetylsalicylic acid) versus non-aspirin NSAIDs and whether the result was derived from a pre-specified endpoint or post hoc subgroup analysis. Current evidence suggests that H. pylori eradication reduces the ulcer risk for patients who are about to start receiving NSAIDs but not for those who are already on long-term NSAID therapy. Since treatment with a proton pump inhibitor (PPI) worsens H. pylori-associated corpus gastritis, H. pylori should be tested for, and eradicated if present, before starting long-term prophylaxis with PPIs. Patients with H. pylori infection and a history of ulcer complications who require NSAIDs should receive concomitant PPIs or misoprostol after curing the infection. Among patients receiving low-dose aspirin, who have H. pylori infection and previous ulcer complications, long-term treatment with a PPI further reduces the risk of complicated ulcers if H. pylori eradication fails or if patients use concomitant non-aspirin NSAIDs. Current data on the gastric safety of COX-2 selective NSAIDs in H. pylori-infected patients are conflicting. Limited data suggest that the gastroduodenal sparing effect of rofecoxib is negated by H. pylori infection in patients who have had prior upper gastrointestinal events. In light of potential cardiovascular risk with COX-2 selective NSAIDs, it is important to weigh the potential adverse effects against the benefits for an individual patient.     

Serum gastrin and chromogranin A during medium- and long-term acid suppressive therapy: a case-control study

BACKGROUND: Serum chromogranin A (CgA) is regarded as a reliable marker of neuroendocrine proliferation. We previously described increased serum CgA levels during short-term profound gastric acid inhibition. AIM: To investigate serum gastrin and CgA levels in dyspeptic patients during continuous medium- (6 weeks to 1 year), or long-term (1-8 years) gastric acid suppressive therapy. PATIENTS AND METHODS: 114 consecutive dyspeptic patients referred for upper gastrointestinal endoscopy were enrolled in a cross-sectional, case-control study [62 patients on continuous antisecretory therapy, either with proton pump inhibitors (n = 47) or H2-receptor antagonists (H2RA) (n = 15) for gastro-oesophageal reflux disease with or without Barrett's oesophagus or functional dyspepsia, and 52 age- and sex-matched patients without medical acid inhibition and with normal endoscopic findings (control group)]. Omeprazole doses ranged from 20 mg to 80 mg daily and ranitidine from 150 mg to 450 mg daily. Fasting serum CgA and serum gastrin levels were measured by radioimmunoassay (reference values: serum CgA < 4.0 nmol/L; serum gastrin < 85 ng/L). RESULTS: Fasting serum CgA levels positively correlated with serum gastrin in the entire study population (r = 0. 55, P = 0.0001). Median serum CgA values were higher in patients treated with a proton pump inhibitor than H2RA [2.8 (2.0-5.9) nmol/L vs. 2 (1.9-2.3) nmol/L, P < 0.002] and controls [2.8 (2.0-5.9) nmol/L vs. 1.8 (1.5-2.2) nmol/L, P < 0.0001) and did not differ between patients treated with H2RA or controls. Serum gastrin and CgA levels in patients on proton pump inhibitor therapy positively correlated with the degree and duration of acid inhibition. Patients on long-term proton pump inhibitor therapy had significantly higher fasting serum gastrin and CgA than those on medium-term proton pump inhibitor therapy [127 (73-217) ng/L vs. 49 (29-78) ng/L, P < 0.0001 and 4.8 (2.8-8) ng/L vs. 2.1 (1.9-2.6) ng/L, P < 0.001]. No such relation was found in patients on medium- vs. long-term H2RA. Overall, patients with positive Helicobacter pylori serology had higher serum gastrin and CgA levels than those with negative H. pylori serology [51 (27-119) ng/L vs. 27 (14-79) ng/L, P = 0.01, 2.4 (1.9-3.4) nmol/L vs. 2.0 (1.7-2.5) nmol/L, P = 0.05]. CONCLUSIONS: During long-term continuous proton pump inhibitor treatment, serum gastrin and CgA levels are significantly elevated compared to H2RA treatment and nontreated dyspeptic controls. H. pylori infection seems to affect gastric ECL cell secretory function. Increased serum CgA values during long-term profound gastric acid inhibition could reflect either gastric enterochromaffin-like cell hyperfunction or proliferative changes.     

Proton pump inhibitor therapy in gastro-oesophageal reflux disease decreases the oesophageal immune response but does not reduce the formation of DNA adducts

Background  Chronic oesophageal inflammation and related oxidative stress are important in the pathogenesis of erosive oesophagitis (EO) and its malignant progression.
Aim  To study the effect of proton pump inhibitors (PPIs) on oesophageal cellular immune response and oxidative damage in EO patients.
Methods  Forty gastro-oesophageal reflux disease (GERD) patients [non-erosive reflux disease (NERD): 15, EO: 25] were included, after 7 days off antisuppressive drugs. EO patients were randomized to 20-mg rabeprazole once daily for either 4 or 8 weeks with baseline and follow-up endoscopy with distal oesophageal biopsies. T lymphocytes, macrophages and mast cells were quantified by immunohistochemistry. DNA adducts were measured by analysis of 8-oxo-deoxyguanosine levels.
Results  Erosive oesophagitis patients had more T lymphocytes and CD8⁺ T lymphocytes in squamous epithelium than NERD patients ( P  = 0.001, P  = 0.002, respectively). Levels of DNA adducts between both groups were, however, not different ( P  = 0.99). Four- and eight-week rabeprazole treatment in EO patients resulted in a significant decrease in number of T lymphocytes and CD8⁺ T lymphocytes (all P  < 0.05). PPIs did not, however, affect levels of DNA adducts.
Conclusions  Short-term PPI therapy in EO patients reduces the oesophageal cellular immune response, but does not change oxidative damage. PPI therapy may therefore not be effective in reducing the risk of oesophageal cancer in GERD patients.